The present invention in general relates to a locking mechanism for rotatably mounted members. The mechanism may be disposed in a locked condition for securing the members at one or more preselected angular relationships, or actuated to a release condition in which the members are free to rotate.
A locking mechanism capable of the above-mentioned operation is useful in a variety of applications. For successful employment, the locking mechanism should be of a relatively compact structure, providing a positive locking action together with quick releasability, and should provide long, reliable and trouble-free operation.
In general, these objectives are provided in accordance with the present invention by mounting a movable detent locking assembly including movable detents such as ball detents within a rotatably positionable member. Such member is in turn pivotally secured to a support member having cooperating indentations. The support member is formed with a wall portion or portions coextensive and in close proximity with the rotational path of the ball detents carried by the positionable member so as to captivate and maintain the ball detents in their retracted condition during the unlocked, rotational movement of the members.
As the positionable member is rotated to approach the locked angular orientation, the ball detents are automatically forced outwardly by a spring bias to their protruding, locked condition seated within the indentations of the support member. A release mechanism is provided for overcoming the spring bias of the ball detent assembly and allowing the ball detents to be released to their retracted condition to unlock the positionable member and permit rotation thereof.
In one embodiment of the present invention as disclosed herein, the positionable member is provided in the form of an elongated, load bearing strut member having one of its ends rotatably or pivotally mounted to a support member. The ball detent locking assembly is advantageously carried within a hollow interior portion of the elongated strut with the ball detents being disposed for cooperating with indentations formed in the support. The indentations are disposed so as to afford different locked angular relationships between the strut and the support. In one example, the strut member is advantageously employed to hold open an aircraft hatch. For this purpose, the strut is rotatable between a locked, out-of-the-way stowed angular position and an angular position in which the strut serves as a load bearing member for supporting the open hatch.
In still another embodiment of the invention, the relatively rotatable members and ball detent locking mechanism provide a lockable, collapsible handle for a rack mounted, semi-portable instrumentation chassis or the like. In this case, the handle is rotatable between a collapsed, locked condition in which the chassis is simultaneously latched or locked to the supporting rack, and an extended, locked condition in which the handle is displaced outwardly for convenient manual grasping and transporting of the chassis. A push-button manual release actuator is provided therewith for releasing the handle from either of its locked, angular positions to afford rotation to the other position.
Still another embodiment of the present invention utilizes the relatively rotatable, lockable members to form a collapsible, manually engageable crank handle. A portion of the crank serves as the support member to which a manually engageable crank handle is pivotally mounted for rotation between a locked, recessed position and a locked, extended position for manual grasping and crank operation. Again, a push-button finger release actuator may be provided as disclosed herein for releasing the handle from the locked, angular orientations.
Another embodiment of the present invention takes the form of a manually operated latch mechanism in which a manually engageable portion of the latch is pivotally mounted to a support member for rotation between latched and unlatched angular positions. The manually engageable and rotatable component of the latch carries the ball detent locking assembly for rotation of the ball detents to and from a locked, angular relationship with indentations formed in the latch support member. As disclosed herein, the indentations formed on the support member may be positioned so as to lock the manually rotatable member in the same angular condition in which the latch itself is closed. As a safety feature, the release mechanism may be constructed so as to be actuated only by a suitably shaped release tool.
These and further embodiments of the present invention and further advantages and features thereof are described more fully herein. The following description is to be read in conjunction with the appended drawings of the exemplary embodiments.